Stray Light Analysis

161 Advantages of manual irrigation system

i. Manual irrigation system does not require technical skill to operate it ii. Water is very much economically used

iii. Evaporation is greatly minimized

iv. Leaching (loss of nutrients through washing down the soil) is greatly reduced .

v. It is a cheap method of irrigation practice to carryout Disadvantages of manual irrigation system

i. The method cannot be used to irrigate a large area of farm.

ii. It involves the direct and too much involvement of human labour

iii. Due to man‟s nature, irrigating the farm may not be properly carried out.

iv. In the event of pest outbreak, the system cannot be used.

v. The quantity of water applied per stand may not be in commensuration of the plant needs, such may be the case where tree crops are to be irrigated.

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irrigation system. As many as the areas occupied by ridges and field channels go a far way in the disruption of the system. The method impedes surface drainage.

ii. Labour shortage: The labour requirement is of two folds. They are the skilled and unskilled labour required for the construction and operation of the irrigation system. The skilled Engineers or technicians as well as the unskilled workers are unavailable. Their unavailability pose a serious challenge to those who would have wanted to construct an irrigation facility in their farms.

iii. Type of crop planted: The type of crop that is being planted is another factor that render challenges to irrigation farming. There are some types of crops and cropping system that do not allow particular irrigation system to be constructed in the farmers plot and so discourages the farmer from carrying out the system.

iv. Unsuitability to some crops: There are some types of crops that do not do well in irrigated farms. Such crops are not suitable for irrigation use because they are sensitive to wet soil conditions around the stem.

v. Chance of backflow into water source: There are instances where the water that is being pumped may experience a backflow. This condition may arise due to a technical issue, and once not detected on time may end up resulting to damages to the crops that were supposed to be irrigated.

vi. Insoluble fertilizers are not suitable: There are some types of fertilizers that are not suitable for the use of irrigation practice. Such fertilizer include super phosphate. In this instance, the use of irrigation does not help matter in dissolving the fertilizer for the uptake of plants roots.

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vi. Corrosive effect of fertilizer: There are some instances where corrosion of the tube or pipe supplying water may become corroded. In a gradual process if not checked, it will lead to the destruction of the pipe and a collapse of the system.

vii. Destruction of the pipe line: In some cases, fertilizers like phosphate may get precipitated in the pipe line and dripper due to pH reaction and this will lead to serious effect such as destruction of the system6. High cost

viii. Malfunctioning of the irrigation system: While irrigation has provided a number of important benefits, some potential drawbacks are imminent. Such drawbacks may include over watering or under-watering of the farm. In any of the cases, there effects that emanates from it.

these are expressed in details below:

Under-watering may result in:

 Loss in market value through yield reduction

 Reduction in fruit size and quality Over-Watering may result in:

 Unwanted vegetative growth

 Losses of valuable water to the water-table

 Irrigation water travelling over soil can cause erosion. The excessive displacement of the top soil can also affect soil fertility (and hence crop yields), it may also clog drainage ditches and streams (silting), harm aquatic habitats, foul waters used for recreational activities, and increases the need for water treatments.

 Irrigation can cause pesticides, pathogens and weeds to spread during irrigation

 Cause runoff

 Increased operational costs (labour, pumping, cost of water)

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 Leaching of nutrients (eg. salt, phosphorus) may lead to algal growth, salinity an nitrate build ups (poisoning) elsewhere in the catchment

 Downgraded product quality and reduced yield.

 Higher operational costs for the producer (hence, reduced profits)

 Pressure on water resources with the Increasing demand for water use by urban dwellers

4.0 Conclusion

The study examined the different types of irrigation system that are prevalent in our farms. The study also found that different conditions actually influence the different types of irrigation systems in our farms. The types discussed were seven in number, though some of them also have sub systems under them. What is paramount is that different conditions suit different types of irrigation systems. The unit revealed some of the limitations or challenges plaguing the construction and use of irrigation systems in our farms.

5.0 Summary

The unit unraveled the different types of irrigation systems that are prevalent in our farms. The sub-types of the major systems were also studied. The factors affecting the functioning of the different irrigation systems were also disclosed.

6.0 Tutor-Marked Assignment

i. List five (5) types of irrigation systems a commercial farmer can construct and practice in his/her farm.

ii. Discuss the five (5) types of irrigation systems mentioned above, a commercial farmer can construct and practice in his/her farm.

iii. Mention three (3) different advantages and disadvantages of drip/trickle irrigation system.

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iv. Explain, giving four (4) reasons why the drip/trickle irrigation system would be preferred to the flooding irrigation system.

v. State two (2) effects of under and over-watering of our farms.

vi. Explain five (5) major challenges plaguing irrigation systems in our farms.

7.0 References

About Irrigation | Irrigation | Soil and water | Farm ...

agriculture.vic.gov.au › agriculture › farm-management. Retrieved on 13^th June, 2020 Irrigation–Principles and Practices - ucsc casfs

casfs.ucsc.edu › PDF-downloads › 1.5-irrigation.pdf. Retrieved on 13^th June, 2020

Iwena, A.O. (2018). Irrigation Agriculture in the Nile Basin and the Niger Basin. In: Essential Geography. Tonad Publishers Limited. PP 529 - 533

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Unit 3: Factors Determining Types of Irrigation Farming and Source of Irrigation Farming